A variety of modular connector assemblies are used to electrically couple electrical signals between the ends of electrical conductors contained in electrical cables and electrical contacts of electrical circuitry of terminal equipment connected to the ends of the cables. A modular connector assembly has a plug that terminates the end of the electrical cable and a jack that mates with the plug. The exterior surface of the plug and the interior surface of the jack have mating features located on them that mate with each other to removably interlock the plug inside of the jack. When the plug is interlocked in a mating relationship with the jack, respective electrical contacts of the plug are in contact with respective electrical contacts of the jack. The electrical contacts of the plug are electrically coupled with the ends of respective electrical conductors of the cable. Similarly, the electrical contacts of the jack are electrically coupled with respective electrical contacts of electrical circuitry of the terminal equipment. Through all of these electrical connections, electrical signals being carried on the electrical conductors of the cable are electrically coupled to the electrical circuitry of the terminal equipment, and vice versa.
One type of modular connector assembly that is well known in the communications industry is an eight position, eight contact (8P8C) modular connector assembly. The 8P8C modular connector assembly is often used with twisted copper pairs to communicate electrical data signals over Ethernet-based communications networks. In Ethernet-based communications networks, the electrical contacts and other circuitry of the 8P8C connector assembly are configured to comply with the RJ-45 wiring standards, which are called the T-568A and T-568B wiring standards. Because these types of modular connector assemblies are made to comply with the RJ-45 wiring standards when they are manufactured for use in Ethernet-based communications networks, they are often referred to as RJ-45 connectors.
Ethernet-based communications networks currently have the capability of carrying electrical data signals at data rates in excess of 1 gigabits per second (Gb/s). Although optical communications links are currently capable of operating at date rates of 10 Gb/s over distances of up to about 100 meters (m), the use of such optical links generally has not spread into areas occupied by high-speed Ethernet-based networks. One reason that the use of optical links has not spread into this space is that the costs of manufacturing pluggable optical modular connector assemblies that can operate at these data rates are much higher than the costs of manufacturing 8P8C modular connector assemblies that operate at these data rates. Another reason that the use of optical links has not spread into this space is that there are currently no optical solutions that have backwards compatibility to the existing electrical Ethernet solutions. Although it is possible to design electrical connections that operate at data rates higher than 1 Gb/s using 8P8C modular connectors that implement the RJ-45 wiring standard, such connections would consume much more power than optical connections operating at the same data rate. In addition, the complexity of the design for such high data rate electrical connections would result in the connections being significantly more expensive than those that operate at 1 Gb/s. Furthermore, a new cabling scheme with higher costs would be required to propagate the data signals at data rates higher than 1 Gb/s over distances of about 100 meters (m).
There are currently a large number of servers and other equipment that have 8P8C modular connectors that have electrical contacts and circuitry configured in accordance with the RJ-45 standard. It would be desirable to provide a modular connector assembly that provides both optical and electrical communications capabilities and that is backwards compatible with existing 8P8C modular connector assemblies that implement RJ-45 wiring standards.